Over recent years, hybrid vehicles, which use both an engine and a motor as a drive source, and electric vehicles, which use a motor, have become popular vehicle types as an alternative to engine vehicles, which are driven by only an engine. Such an electric vehicle uses a battery that must be charged when the battery voltage becomes low. For example, the battery may be charged by connecting an input of an external charging device, such as a power feed connector, to a household electrical outlet (utility power, alternating current of 100 V) and connecting the output of the charging device to a charging connector of the vehicle. As another option, an electric vehicle may be connected to and charged at an electricity station.
Furthermore, regardless of whether the vehicle is an engine vehicle or an electric vehicle, antitheft measures must be taken. Patent Document 1 describes an example of an antitheft prevention technique that is unique to electric vehicles. In an electric vehicle, a battery is used as a drive source. With the technique described in Patent Document 1, information related to the charging of the vehicle, such as the state of charge of the battery, is collected as driving information. The collected driving information is transmitted to a management center. The management center tracks a stolen vehicle by determining the location of the vehicle from such driving information.
However, even when the state of charge of the stolen vehicle becomes low, the battery of the stolen vehicle can be charged at an electricity station that is located anywhere. Therefore, the battery of the stolen vehicle can be charged periodically. Since the stolen vehicle, which may be charged periodically, can be driven anywhere, it would be extremely difficult to track the stolen vehicle even with the technique described in Patent Document 1.
Patent Document 1: Japanese Laid-Open Patent Publication No. 2005-115667